selftests: pmtu: maximum MTU for vti4 is 2^16-1-20

[ Upstream commit 902b5417f28d955cdb4898df6ffaab15f56c5cff ]

Since commit 82612de1c98e ("ip_tunnel: restore binding to ifaces with a
large mtu"), the maximum MTU for vti4 is based on IP_MAX_MTU instead of
the mysterious constant 0xFFF8.  This makes this selftest fail.

Fixes: 82612de1c98e ("ip_tunnel: restore binding to ifaces with a large mtu")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh
index f8cc38afffa2e6a35dd316a40e2493356c16063c..0ecf2609b9a4ff69c6144ca4a2afb2f1b601cb84 100755 (executable)
--- a/tools/testing/selftests/net/pmtu.sh
+++ b/tools/testing/selftests/net/pmtu.sh
@@ -334,7 +334,7 @@ test_pmtu_vti4_link_add_mtu() {
        fail=0
 
        min=68
-       max=$((65528 - 20))
+       max=$((65535 - 20))
        # Check invalid values first
        for v in $((min - 1)) $((max + 1)); do
                ${ns_a} ip link add vti4_a mtu ${v} type vti local ${veth4_a_addr} remote ${veth4_b_addr} key 10 2>/dev/null